<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			.qw:hover{
				animation: my 2s;
			}
			@keyframes my{
				0%{
					margin: 0;
				}
				50%{
					margin-top: 5px;
				}
				100%{
					margin-top: -5px;
				}
			}
		</style>
	</head>
	<body>
		<div class="qw">你好</div>
	</body>
</html>
